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(No Model.) v 3 Shets-Shet 1.

J. E. GERMAIN. MACHINE FOR ROUGE GRINDING OPTICAL GLASSES. No. 550,788. T Patented Dec. 3, 1895.

(No Model.) 3 Sheets-Sheet 2.

J. E. GERMAIN. MACHINE FOR'ROUGH GRINDING OPTIGAL GLASSES;

No. 550,788. Patented Dec. 3, 1895.

FIF

W] NESSES' M/VE/V'TQR ANDREW BYGRAHAM,PMGTULI'MQWASHINFI'DMDC.

(No Model.) 3 Sheets-Sheet 3.

. J. E. GER'MAIN. MACHINE FOR ROUGH GRINDING OPTICAL GLASSES.

No. 550,788. y Patented Dec. 3, 1895.

AN DREW B,GRAHAM4 PHUTd-LITHQWASHINGTON. D C.

UNTTE STATES 'ATENT FFICE.

JULES EUGENE GERMAIN, OF PARIS, FRANCE, ASSIGNOR TO LA socIETE PARISIENNE DE vEREEEIE OPTIQUE, or SAME PLACE.

MACHINE FOR ROUGH-GRINDING OPTICAL GLASSES.

SPECIFICATION forming part of Letters Patent No. 550,788, dated December 3, 1895.

Application filed April 18, 1895- Serial No. 546,234. (No model.)

To (LZZ whom it may concern.-

Be it known that I, JULEs EUGENE GER- MAIN, a citizen of the Republic of France, residing at Paris, in the Republic of France, have invented certain new and useful Improvements in Machines for Rough-Grinding Optical Glasses, of which the following is a specification.

It is customary to first round off the edges of the glass-blanks, and then in a separate machine the blanks have to be rough-ground on their two faces, so as to prepare them for the final finish which they have to receive. This operation of rough-grinding .is accomplished mechanically by means of a machine which forms the subject-matter of the present invention and which machine is represented in the accompanying drawings, in which- Figure 1 is a side elevation,partly in section, of my improved machine for rough-grinding glass-blanks. Fig. 2 is a horizontal section at the lower part of the machine, drawn on line 2 2, Fig. 1. Fig. 3 is a horizontal section of the actuating-box and the hood of the machine. Fig. 4 is a vertical diagonal section of the same on line 4 4:, Fig. 3; and Fig. 5 is a modified construction of the machine. I

Similar letters and numerals of reference indicate corresponding parts.

The glass-blanks are attached by means of suitable paste or pitch on the convex surface of a hemispherical dop B, which is located 011 the lower end of a vertical shaft 0, that is supported in suitable bearings O at its upper end and is provided with a fast and loose pulley D D, respectively, by which motion is transmitted to the shaft 0. A grooved wheel E is arranged on the upper end of the shaft 0 and engaged by the forked end of a pivoted lever G, by means of which the shaft 0 can be moved, so as to permit the changing of the dop B when the same is necessary.

The dop B is surrounded by and placed. in an internally-grooved cup H, which is provided with "a sheet-metal rim h, extending above the dop. The forms of the dop B and the cup Hthat,is to say, theiradjacent surfaces-"correspond to the curvature which is to be given to the-faces of the glass-blanks, so that in all cases when the dop and cup are spherical they are not arranged concentrically one in the other, but slightly eccentric, for if it were otherwise a small portion of the glass-blanks fixed on the surface of the dop B in the center of the same would be ground, while the others near the edge of the same would not be regularly ground off. The center of the cup H should be slightly higher than the center of the dop B,-but in the same vertical line therewith, so as to provide for the compound motion which is imparted to the cup, as will appear hereinafter.

The cup I-I ismounted on the upper end of a shaft I, which is secured at its lower end in a square socket J, that is constructed in the following manner: The socket J has a central vertical screw-threaded opening to receive the screw-threaded lower end of the shaft I and is provided at each of its four sides with a lateral hole J, through which passes the shank or gudgeon of a check K, which is formed at three of its sides with inclined planes 70 k respectively. The inner ends ofv the shanks of the cheeks K press against an antifriction-ball L, which can rest between two balls L L of which the upper one, L is located in the socket J above the holes J, while the lower one is located at and projects from the lower end of the socket J, so as to support thereby the shaft I on the bottom of a square box M. For the purpose of centering the shaft in the box M the bottom of the same has a central concavity m to receive the ball L. The boX M is provided within each of its sides with three antifriction-rollers N N N, which are located so as to correspond to the three inclined faces of the cheeks K,

the rollers N N being placed adjacent to the inclined faces 70 Jo, respectively, of the cheeks and the roller N adjacent to the face 70 of the same, By means of this disposition of the described parts it will be readily understood that the shaft I and thereby the socket J are made to rotate around the point of contact of the ball with the bottom of the boX M, and during this motion the cheeks K of the socket J are placed in contact with the antifriction-rollers N N N by means of which the frictional contact with the cheeks tened thereto by a set-screw v.

by means of a hood or cover 0, as shown in Figs. 1 and 4, which is fixed centrally to the shaft I and is connected by means of helical springs P, attached to the corners of the shell 0, with arms Q, that project from the under side of the box M. The shank m of the box H is provided at its lower end with a longitudinal cavity, which receives an antifriction-ball m by which the box is supported on a vertical post R, which extends into the cavity of the shank m. The post R is mounted at its lower end 011 a slide R", which is retained in guideways R fixed on a plate S. (Shown in Figs. 1 and 4.) By means of a screw-nut s the position of the slide R in the ways R can be changed at will and thereby the same adjusted relatively to the center of the horizontal plate S, which is mounted on the upper end of a vertical shaft S, supported in bearings of a table Y. To the shaft S are applied fixed and loose pulleys T T, by which rotary motion is imparted to the shaft S and plate S. The lower end of the shaft S is supported in a step-bearing U, provided with an antifriction-ball in its socket and with an adj Listing-screw U, which passes through a frame Z and is adjusted by jam-nuts U so as to raise or lower the stepbearing.

The machine receives the following two mo tions: The first motion is imparted to the shaft C by means of the 1notion-transmitting pulleys D D and by the shaft to the dop B. This motion has no action on the lower members of the machine. A second rotary motion is imparted to the plate S by the motiontransmitting pulley T. This movement exerts no rotary influence on the dopB and acts only on the axial cup H in the following man ner: The shaft R, which is connected to the plate S, describes a circle, which has for its radius the distance that separates the shaft R from the center of the plate S. The box M is compelled to follow this circular movement and is prevented from axially rotating. It is mounted in an arm V, the object of which will be directly described, it being suificient to remark that by the simple interposition of an antifriction-ball between the box M and the shaft R the former cannot turn on its axis, but is compelled to follow the circular movement of the shaft R. The antifriction-ball L in the box M is compelled to follow the described movement in a circle around the axis of the plate S, and the shaft I, which rests only in the box M by means of the antifriction-ball L, is compelled to rotate in conical form like arotary pendulum, while the cup II receives an alternating oscillating motion.

As before stated, the box M is prevented from turning on its axis by means of the arm V. For producing this effect the arm V is provided with a ring-shaped end, which encircles the shank m of the box M and is fas- The arm V follows the rotary motion of the box M around the axis of the plate S and turns by its slotted outer end around an antifriction-sleeve X, that is mounted on a journal-pin attached at the upper end of a pillar X to the table Y. Converging rods W extend from two corners of the hood or cover 0 to the outer ends of the arm V, so as to steady the movement of the cover 0 and reduce thereby its wabbling motion.

hen the motion of the-machine is interrupted, the shaft 0 is raised, and to its lower end is applied a dop B, on the outer surface of which are secured byasuitable cement the glass-blanks that are to be roughened. The axle (J is then lowered until the dop B is placed in the cup H, after which is introduced between the two a very fine grindingpowder mixed with a sufiicient quantity of water. The machine is now. set in motion, and when the grinding is completed all that is necessary is to raise the shaft 0 and replace the dop B by another one. By this means one attendant can attend to anumber of rough-grinding machines, as hand labor is thereby dispensed with to a verylarge extent.

In Fig. 5 is shown a modification of the machine. The plate S is provided with a recess in its under side, so as to form a flange S which has teeth 3 at its inner edge. The shaft S carries at its upper end a gear-wheel 1, which engages a pinion 2, which is mounted on a short axle 2, attached to the plate S. The pinion 2 meshes again with the interiorlytoothed flange S of the plate S. Motion is imparted to the plate S in the same mannor as in the machine before described. The guideways R on the plate S are the same as before, but the box M is replaced by a universal joint 4, which imparts to the cup H the same oscillating motion before described. Otherwise the motion imparted to the body and the operation of the same are the same as in the construction first described.

By the machine described the circular glassblanks are worked on their faces in such a manner that they assume gradually the final form which has to be imparted to the same,

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. In a machine for rough-grinding optical glasses, the combination of a rotary dop, a cup in which said dop rotates, a shaft for supporting said cup, at box in which the lower end of said shaft is supported, and means for moving said box in a circular path, substantially as set forth.

2. In a machine for rou gh-grinding optical glasses, the combination of a dop, a cup, a shaft for supporting the cup, a box, means for causing said box to move in a circular 8. In a machine for rough-grinding optical glasses, the combination of a dop, a cup in which said dop rotates, a shaft for supporting the cup, a box in which'the lower end of the shaft is supported, said box having a shank provided with alongitudinal bore, and a rotary plate provided with an eccentric shaft, which fits loosely into the bore of said shank, substantially as set forth.

4. In a machine for rough-grinding optical glasses, the combination of a dop, a cup in which the same rotates, a shaft for supporting the cup, a box provided with a shank, said box supporting the lower end of the shaft, a rotary plate provided with a guideway, a slide guided in said way, an eccentric shaft projecting from the slide and extending into a bore in the shank of the box, and an anti-friction ball arranged in said bore, substantially as set forth.

5. I11 a machine for rough-grinding optical glasses, the combination of a dop, a cup, a shaft for supporting the cup, a box provided with a shank, said box supporting the lower end of said shaft, a rotary plate provided with an eccentric shaft extending into a longitudinal bore of said shaft, and an oscillating guide-arm secured to the shank and provided with guiding means, substantially as set forth.

6. In a machine for rough-grinding optical glasses, the combination of a dop, a cup in which the dop rotates, a shaft for supporting the cup, a box for supporting the lower end of the shaft, means for moving said box in a circular path, a cover or hood extending over the box and secured to the shaft, arms proj ecting from the box, and springs connecting the arms with the cover or hood, substantially as set forth.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

JULES EUGENE eEEMAiN.

\Vitnesses CLYDE SHROPSHIRE, JOSEPH LACOSTE. 

